Positive impact of oral hydroxychloroquine and povidone-iodine throat spray for COVID-19 prophylaxis: An open-label randomized trial

Cyclodextrin-based iodophors with high iodine retention in solid state and in dilute solutions

Iodine is a broad-spectrum antiseptic with the advantage of not inducing bacterial resistance, but its use is limited by volatility. This issue can be overcome by using "iodophors", which are molecular systems able to retain iodine and provide its sustained release. Cyclodextrins have proven effective in stabilizing iodine in solution through the formation of complexes, the preparation of which in solid form could offer additional benefits in terms of handling and storage. A series of cyclodextrins (CD) were tested for their ability to form solid complexes with iodine and it was found that the addition of potassium iodide in the solid-state preparation of the complexes significantly increases both iodine incorporation and long-term stability compared to the solids obtained without added potassium iodide. Dilute aqueous solutions of the obtained complexes were monitored for their iodine content in different conditions and excellent stability was observed in some cases. Furthermore, these cyclodextrin‑iodine complexes showed no cytotoxic effects on human corneal epithelial cells (HCE-2) while displayed very high antimicrobial (against Staphylococcus epidermis) and antiviral (against Human adenovirus 5) activities. These findings highlight the potential of cyclodextrins as a versatile platform for the development of solid iodophors as an alternative to the traditional povidone-iodide formulation.

Ivermectin as a Treatment Modality in COVID-19 Patients: A Systematic Review and Meta-Analysis of Up-To-Date RCTs

The objective of this systematic review and meta-analysis is to assess the efficacy and safety of Ivermectin compared to placebo or standard of care for the treatment and prevention of COVID-19 disease. Literature search was carried out in PubMed, Scopus, and google scholar. Clinical trial registries (clinical trail.gov) and preprint servers (Medrxiv) were also searched for registered and preprint data respectively. Mortality, Clinical recovery, Clinical worsening, duration of hospital stay, and adverse events were considered as primary outcomes while viral clearance is considered as a secondary outcome. Revised Cochrane risk of bias assessment tool was used to assess the risk of bias. Random effect meta-analysis was carried out for all the outcomes. GRADE was used to rate the certainty of evidence. A total of 19 RCTs with 1111 patients were included in the analysis. Ivermectin use did was not associated with a reduction in the incidence of mortality, duration of hospitalization, clinical worsening, and incidence of adverse events nor it was associated with an increase in clinical improvement compared to either placebo or standard of care. Ivermectin also did not show any reduction in viral clearance compared to both placebo or standard of care and this was associated with substantial inconsistency. The overall certainty of the evidence was very low to low. Based on the very low to low certainty of the evidence, we consider Ivermectin ineffective in the management of COVID-19 disease, both as treatment and prophylaxis.

The efficacy and safety of hydroxychloroquine at different doses and courses for COVID-19 prevention: a systematic review and network meta-analysis

BACKGROUND

The optimal strategy for using hydroxychloroquine to prevent coronavirus disease 2019 (COVID-19) in patients, either before or after exposure, remains unclear. We evaluated the safety and efficacy of different doses and treatment durations of hydroxychloroquine for COVID-19 prevention.

METHOD

Databases including PubMed, Web of Science, Cochrane Library, EMBASE, Medline, and ClinicalTrials.gov were systematically searched for randomized controlled trials (RCTs) comparing different doses of hydroxychloroquine for COVID-19 prevention, from their inception to February 2024.

RESULTS

A total of 20 RCTs involving 12,372 patients were included. Meta-analysis results showed no significant difference between the hydroxychloroquine and control groups in reducing the incidence of syndrome coronavirus type 2 (SARS-CoV-2) positivity (OR = 0.83, 95% CI = 0.67, 1.03). However, the subgroup receiving a daily dose of 200-400 mg (OR = 0.62, 95% CI = 0.51, 0.75) and a treatment duration of 5-8 weeks (OR = 0.52, 95% CI = 0.31, 0.88) showed statistically significant reductions in SARS-CoV-2 positivity. According to the surface under the cumulative ranking curve (SUCRA), the most effective intervention was a 200-400 mg dose for 5-8 weeks.  .

CONCLUSIONS

A hydroxychloroquine dose of 200-400 mg for a duration of 5-8 weeks may moderately reduce the risk of COVID-19 with a relatively low risk of adverse events.

Hybrid immunity augments cross-variant protection against COVID-19 among immunocompromised individuals

BACKGROUND

Immunity to SARS-CoV-2 vaccination and infection differs considerably among individuals. We investigate the critical pathways that influence vaccine-induced cross-variant serological immunity among individuals at high-risk of COVID-19 complications.

METHODS

Neutralizing antibodies to the wild-type SARS-CoV-2 virus and its variants (Beta, Gamma, Delta and Omicron) were analyzed in patients with autoimmune diseases, chronic comorbidities (multimorbidity), and healthy controls. Antibody levels were assessed at baseline and at different intervals up to 12 months following primary and booster vaccination with either BNT162b2 or mRNA-1273. Immunity induced by vaccination with and without infection (hybrid immunity) was compared with that of unvaccinated individuals with recent SARS-CoV-2 infection. Plasma cytokines were analyzed to investigate variations in antibody production following vaccination.

RESULTS

Patients with autoimmune diseases (n = 137) produced lesser antibodies to the wild-type SARS-CoV-2 virus and its variants compared with those in the multimorbidity (n = 153) and healthy groups (n = 229); antibody levels were significantly lower in patients with neuromyelitis optica and those on prednisolone, mycophenolate or rituximab treatment. Multivariate logistic regression analysis identified neuromyelitis optica (odds ratio 8.20, 95% CI 1.68-39.9) and mycophenolate (13.69, 3.78-49.5) as significant predictors of a poorer antibody response to vaccination (i.e, neutralizing antibody <40%). Infected participants exhibited antibody levels that were 28.7% higher (95% CI 24.7-32.7) compared to non-infected participants six months after receiving a booster vaccination. Individuals infected during the Delta outbreak generated cross-protective neutralizing antibodies against the Omicron variant in quantities comparable to those observed after infection with the Omicron variant itself. In contrast, unvaccinated individuals recently infected with the wild-type (n = 2390) consistently displayed lower levels of neutralizing antibodies against both the wild-type virus and other variants. Pathway analyses suggested an inverse relationship between baseline T cell subsets and antibody production following vaccination.

CONCLUSION

Hybrid immunity confers a robust protection against COVID-19 among immunocompromised individuals.

Evaluation of hydroxychloroquine or chloroquine for the prevention of COVID-19 (COPCOV): A double-blind, randomised, placebo-controlled trial

BACKGROUND

Hydroxychloroquine (HCQ) has proved ineffective in treating patients hospitalised with Coronavirus Disease 2019 (COVID-19), but uncertainty remains over its safety and efficacy in chemoprevention. Previous chemoprevention randomised controlled trials (RCTs) did not individually show benefit of HCQ against COVID-19 and, although meta-analysis did suggest clinical benefit, guidelines recommend against its use.

METHODS AND FINDINGS

Healthy adult participants from the healthcare setting, and later from the community, were enrolled in 26 centres in 11 countries to a double-blind, placebo-controlled, randomised trial of COVID-19 chemoprevention. HCQ was evaluated in Europe and Africa, and chloroquine (CQ) was evaluated in Asia, (both base equivalent of 155 mg once daily). The primary endpoint was symptomatic COVID-19, confirmed by PCR or seroconversion during the 3-month follow-up period. The secondary and tertiary endpoints were: asymptomatic laboratory-confirmed Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection; severity of COVID-19 symptoms; all-cause PCR-confirmed symptomatic acute respiratory illness (including SARS-CoV-2 infection); participant reported number of workdays lost; genetic and baseline biochemical markers associated with symptomatic COVID-19, respiratory illness and disease severity (not reported here); and health economic analyses of HCQ and CQ prophylaxis on costs and quality of life measures (not reported here). The primary and safety analyses were conducted in the intention-to-treat (ITT) population. Recruitment of 40,000 (20,000 HCQ arm, 20,000 CQ arm) participants was planned but was not possible because of protracted delays resulting from controversies over efficacy and adverse events with HCQ use, vaccine rollout in some countries, and other factors. Between 29 April 2020 and 10 March 2022, 4,652 participants (46% females) were enrolled (HCQ/CQ n = 2,320; placebo n = 2,332). The median (IQR) age was 29 (23 to 39) years. SARS-CoV-2 infections (symptomatic and asymptomatic) occurred in 1,071 (23%) participants. For the primary endpoint the incidence of symptomatic COVID-19 was 240/2,320 in the HCQ/CQ versus 284/2,332 in the placebo arms (risk ratio (RR) 0.85 [95% confidence interval, 0.72 to 1.00; p = 0.05]). For the secondary and tertiary outcomes asymptomatic SARS-CoV-2 infections occurred in 11.5% of HCQ/CQ recipients and 12.0% of placebo recipients: RR: 0.96 (95% CI, 0.82 to 1.12; p = 0.6). There were no differences in the severity of symptoms between the groups and no severe illnesses. HCQ/CQ chemoprevention was associated with fewer PCR-confirmed all-cause respiratory infections (predominantly SARS-CoV-2): RR 0.61 (95% CI, 0.42 to 0.88; p = 0.009) and fewer days lost to work because of illness: 104 days per 1,000 participants over 90 days (95% CI, 12 to 199 days; p < 0.001). The prespecified meta-analysis of all published pre-exposure RCTs indicates that HCQ/CQ prophylaxis provided a moderate protective benefit against symptomatic COVID-19: RR 0.80 (95% CI, 0.71 to 0.91). Both drugs were well tolerated with no drug-related serious adverse events (SAEs). Study limitations include the smaller than planned study size, the relatively low number of PCR-confirmed infections, and the lower comparative accuracy of serology endpoints (in particular, the adapted dried blood spot method) compared to the PCR endpoint. The COPCOV trial was registered with ClinicalTrials.gov; number NCT04303507.

INTERPRETATION

In this large placebo-controlled, double-blind randomised trial, HCQ and CQ were safe and well tolerated in COVID-19 chemoprevention, and there was evidence of moderate protective benefit in a meta-analysis including this trial and similar RCTs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04303507; ISRCTN Registry ISRCTN10207947.

The efficacy and safety of hydroxychloroquine for COVID-19 prophylaxis and clinical assessment: an updated meta-analysis of randomized trials

Background

Coronavirus disease 2019 (COVID-19), a disease that affected tens of millions of people, upended the lives of countless individuals around the globe. The chloroquine (CQ) and its analogue hydroxychloroquine (HCQ) were the most frequently cited as potential treatments and preventatives against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The primary aim of this investigation was to scrutinize the effectiveness and safety of HCQ for COVID-19 prevention and to present powerful evidence and reference for clinical practice.

Methods

PubMed, Ovid and the Cochrane COVID-19 Register of Controlled Trials (CENTRAL) were systematically searched from inception to January 31, 2022. Randomized controlled trials (RCTs) trials that included participants who were SARS-CoV-2 negative at the time of registration were enrolled in this meta-analysis. The intervention group took HCQ or CQ orally. The control group was not blinded by quinine or placebo. Pooled relative risk (RR) of SARS-CoV-2 infection, mortality, hospitalization, adverse events, and compliance were calculated. The software tools utilized for statistical analyses were Stata 14 and Review Manager 5.3.

Results

A total of 9 studies including 7,825 participants were enrolled. Bias of individual studies were assessed as low risk. The pooled RR for SARS-CoV-2 infection was 0.75 [95% confidence interval (CI): 0.68-0.83] (z=-4.01, P<0.0001; I2=11%). The pooled RR for hospitalization was 0.72 (95% CI: 0.35-1.50) (z=0.87, P=0.39; I2=0.0%). The pooled RR for mortality and adverse events were 3.26 (95% CI: 0.13-79.74) (z=0.72, P=0.47; I2=0.0%) and 1.90 (95% CI: 1.20-3.02) (z=2.73, P=0.0063; I2=94%).

Conclusions

Results of this meta-analysis indicated significant impact of HCQ on SARS-CoV-2 infection with higher risk of adverse events. These findings must be considered with caution, and further research is necessary to delineate the specific circumstances where HCQ may be effective for COVID-19 prevention.

Back to the Basics of SARS-CoV-2 Biochemistry: Microvascular Occlusive Glycan Bindings Govern Its Morbidities and Inform Therapeutic Responses

Consistent with the biochemistry of coronaviruses as well established over decades, SARS-CoV-2 makes its initial attachment to host cells through the binding of its spike protein (SP) to sialylated glycans (containing the monosaccharide sialic acid) on the cell surface. The virus can then slide over and enter via ACE2. SARS-CoV-2 SP attaches particularly tightly to the trillions of red blood cells (RBCs), platelets and endothelial cells in the human body, each cell very densely coated with sialic acid surface molecules but having no ACE2 or minimal ACE2. These interlaced attachments trigger the blood cell aggregation, microvascular occlusion and vascular damage that underlie the hypoxia, blood clotting and related morbidities of severe COVID-19. Notably, the two human betacoronaviruses that express a sialic acid-cleaving enzyme are benign, while the other three-SARS, SARS-CoV-2 and MERS-are virulent. RBC aggregation experimentally induced in several animal species using an injected polysaccharide caused most of the same morbidities of severe COVID-19. This glycan biochemistry is key to disentangling controversies that have arisen over the efficacy of certain generic COVID-19 treatment agents and the safety of SP-based COVID-19 vaccines. More broadly, disregard for the active physiological role of RBCs yields unreliable or erroneous reporting of pharmacokinetic parameters as routinely obtained for most drugs and other bioactive agents using detection in plasma, with whole-blood levels being up to 30-fold higher. Appreciation of the active role of RBCs can elucidate the microvascular underpinnings of other health conditions, including cardiovascular disease, and therapeutic opportunities to address them.

Biomarkers of early SARS-CoV-2 infection before the onset of respiratory symptoms

OBJECTIVES

Currently, limited data exist regarding the pathological changes occurring during the incubation phase of SARS-CoV-2 infection. We utilized proteomic analysis to explore changes in the circulatory host response in individuals with SARS-CoV-2 infection before the onset of symptoms.

METHODS

Participants were individuals from a randomized clinical trial of prophylaxis for COVID-19 in a workers' dormitory. Proteomic signatures of blood samples collected within 7 days before symptom onset (incubation group) were compared with those collected >21 days (non-incubation group) to derive candidate biomarkers of incubation. Candidate biomarkers were assessed by comparing levels in the incubation group with both infected individuals (positive controls) and non-infected individuals (negative controls).

RESULTS

The study included men (mean age 34.2 years and standard deviation 7.1) who were divided into three groups: an incubation group consisting of 44 men, and two control groups-positive (n = 56) and negative (n = 67) controls. Through proteomic analysis, we identified 49 proteins that, upon pathway analyses, indicated an upregulation of the renin-angiotensin and innate immune systems during the virus incubation period. Biomarker analyses revealed increased concentrations of plasma angiotensin II (mean 731 vs. 139 pg/mL), angiotensin (1-7) (302 vs. 9 pg/mL), CXCL10 (423 vs. 85 pg/mL), CXCL11 (82.7 vs. 32.1 pg/mL), interferon-gamma (0.49 vs. 0.20 pg/mL), legumain (914 vs. 743 pg/mL), galectin-9 (1443 vs. 836 pg/mL), and tumour necrosis factor (20.3 vs. 17.0 pg/mL) during virus incubation compared with non-infected controls (all p < 0.05). Plasma angiotensin (1-7) exhibited a significant increase before the onset of symptoms when compared with uninfected controls (area under the curve 0.99, sensitivity 0.97, and specificity 0.99).

DISCUSSION

Angiotensin (1-7) could play a crucial role in the progression of symptomatic COVID-19 infection, and its assessment could help identify individuals who would benefit from enhanced monitoring and early antiviral intervention.

Ivermectin for treatment of COVID-19: A systematic review and meta-analysis

The effect of ivermectin (IVM) in treating coronavirus disease 2019 (COVID-19) is still controversial, yet the drug has been widely used in the world. The aim of this review was to systematically evaluate the clinical outcomes of IVM in patients with COVID-19. From inception to June 22, 2023, the PubMed, EMBASE, Web of Science (WOS), and scopus databases were searched for relevant observational studies on the risk of RA in migraineurs. We searched PubMed/Medline, EMBASE, the Cochrane Library, Web of Science, medRxiv, and bioRxiv to collect all relevant publications from inception to June 22, 2023. Primary outcomes were all-cause mortality rate, mechanical ventilation (MV) requirement, PCR negative conversion, and adverse events (AEs). Revman 5.4 was used to assess the risk of bias (RoB) and quality of evidence. Thirty-three RCTs (n = 10,489) were included. No significant difference in all-cause mortality rates or PCR negative conversion between IVM and controls. There were significant differences in MV requirement (RR 0.67, 95% CI 0.47-0.96) and AEs (RR 0.87, 95% CI 0.80-0.95) between the two groups. Ivermectin could reduce the risk of MV requirement and AEs in patients with COVID-19, without increasing other risks. In the absence of a better alternative, clinicians could use it with caution.

Evaluation of weak genotoxicity of hydroxychloroquine in human TK6 cells

Hydroxychloroquine (HCQ), a derivative of chloroquine (CQ), is an antimalarial and antirheumatic drug. Since there is limited data available on the genotoxicity of HCQ, in the current study, we used a battery of in vitro assays to systematically examine the genotoxicity of HCQ in human lymphoblastoid TK6 cells. We first showed that HCQ is not mutagenic in TK6 cells up to 80 μM with or without exogenous metabolic activation. Subsequently, we found that short-term (3-4 h) HCQ treatment did not cause DNA strand breakage as measured by the comet assay and the phosphorylation of histone H2A.X (γH2A.X), and did not induce chromosomal damage as determined by the micronucleus (MN) assay. However, after 24-h treatment, both CQ and HCQ induced comparable and weak DNA damage and MN formation in TK6 cells; upregulated p53 and p53-mediated DNA damage responsive genes; and triggered apoptosis and mitochondrial damage that may partially contribute to the observed MN formation. Using a benchmark dose (BMD) modeling analysis, the lower 95% confidence limit of BMD50 values (BMDL50) for MN induction in TK6 cells were about 19.7 μM for CQ and 16.3 μM for HCQ. These results provide additional information for quantitative genotoxic risk assessment of these drugs.

Sialylated Glycan Bindings from SARS-CoV-2 Spike Protein to Blood and Endothelial Cells Govern the Severe Morbidities of COVID-19

Consistent with well-established biochemical properties of coronaviruses, sialylated glycan attachments between SARS-CoV-2 spike protein (SP) and host cells are key to the virus's pathology. SARS-CoV-2 SP attaches to and aggregates red blood cells (RBCs), as shown in many pre-clinical and clinical studies, causing pulmonary and extrapulmonary microthrombi and hypoxia in severe COVID-19 patients. SARS-CoV-2 SP attachments to the heavily sialylated surfaces of platelets (which, like RBCs, have no ACE2) and endothelial cells (having minimal ACE2) compound this vascular damage. Notably, experimentally induced RBC aggregation in vivo causes the same key morbidities as for severe COVID-19, including microvascular occlusion, blood clots, hypoxia and myocarditis. Key risk factors for COVID-19 morbidity, including older age, diabetes and obesity, are all characterized by markedly increased propensity to RBC clumping. For mammalian species, the degree of clinical susceptibility to COVID-19 correlates to RBC aggregability with p = 0.033. Notably, of the five human betacoronaviruses, the two common cold strains express an enzyme that releases glycan attachments, while the deadly SARS, SARS-CoV-2 and MERS do not, although viral loads for COVID-19 and the two common cold infections are similar. These biochemical insights also explain the previously puzzling clinical efficacy of certain generics against COVID-19 and may support the development of future therapeutic strategies for COVID-19 and long COVID patients.

Efficacy of different mouthwashes against COVID-19: A systematic review and network meta-analysis

To evaluate the effectiveness of antiseptic mouthwashes in reducing SARS-CoV-2 load clinically and in vitro. A systematic electronic search (MEDLINE/Scopus/Cochrane) was conducted to identify prospective clinical and in vitro studies published between 2019 included and 16 June 2023 assessing the effectiveness of mouthwashes in reducing SARS-CoV-2 load in saliva or surrogates. Data were summarized in tables and a network meta-analysis was performed for clinical trials. Thirty-five studies (14 RCTs, 21 in vitro) fulfilled the inclusion criteria. The risk of bias was judged to be high for 2 clinical and 7 in vitro studies. The most commonly test product was chlorhexidine alone or in combination with other active ingredients, followed by povidone-iodine, hydrogen peroxide and cetylpyridinium chloride. Overall, the descriptive analysis revealed the effectiveness of the mouthwashes in decreasing the salivary viral load both clinically and in vitro. Network meta-analysis demonstrated a high degree of heterogeneity. Among these studies, only chlorhexidine 0.20% was associated to a significant Ct increase in the saliva 5 min after rinsing compared to non-active control (p = 0.027). Data from clinical and in vitro studies suggested the antiviral efficacy of commonly used mouthwashes. Large well-balanced trials are needed to identify the best rinsing protocols.

High technology and low technology measures to reduce risk of SARS-CoV-2 transmission

During the coronavirus disease 2019 (COVID-19) pandemic, a variety of low technology and high technology measures have been proposed to reduce the risk for transmission. Identifying those measures likely to be useful in reducing viral transmission without undue expense or potential for adverse effects has been a challenge for infection control programs. The challenge has been compounded by the lack of tools that can be used to assess the risk for viral transmission in different settings. This review discusses practical tools that can be used to assess ventilation and airflow and evaluates some of the low technology and high technology measures that have been proposed as control measures for COVID-19. Some typical questions posed to infection control programs during the pandemic are presented to illustrate real-world application of the concepts being discussed.

Vitamin D and Zinc Supplementation to Improve Treatment Outcomes among COVID-19 Patients in India: Results from a Double-Blind Randomized Placebo-Controlled Trial

BACKGROUND

There remains a need to identify low-cost interventions to improve coronavirus disease 2019 (COVID-19) outcomes. Vitamin D and zinc play a role in respiratory infections and could hold value as part of therapeutic regimens.

OBJECTIVES

To determine the effect of vitamin D or zinc supplementation on recovery from COVID-19.

METHODS

We conducted a double-blind, randomly assigned 2 x 2 factorial placebo-controlled trial with 1:1:1:1 allocation ratio, enrolling nonpregnant adults with COVID-19 from hospitals in Mumbai and Pune, India (NCT04641195). Participants (N = 181) were randomly assigned to vitamin D3 (180,000 IU bolus, then 2000 IU daily), zinc (40 mg daily), vitamin D3 and zinc, or placebo, for 8 wk. Participants were followed until 8 wk. The primary outcome was time to resolution of fever, cough, and shortness of breath. Secondary outcomes were duration of individual symptoms; need for assisted ventilation; duration of hospital stay; all-cause mortality; and blood biomarkers, including nutritional, inflammatory, and immunological markers.

RESULTS

We observed no effect of vitamin D or zinc supplementation on time to resolution of all 3 symptoms [vitamin D hazard ratio (HR): 0.92; 95% confidence interval (95% CI): 0.66, 1.30; P = 0.650; zinc HR: 0.94; 95% CI: 0.67, 1.33; P = 0.745)]. Neither vitamin D nor zinc supplementation was associated with secondary outcomes, except for increased endline serum vitamin D with vitamin D supplementation [median (interquartile range) difference between endline and baseline for vitamin D: 5.3 ng/mL (-2.3 to 13.7); for no vitamin D: -1.4 ng/mL (-5.6 to 3.9); P = 0.003]. We observed nonsignificant increases in serum zinc at endline following zinc supplementation. There was no evidence of interaction between vitamin D and zinc supplementation, no effect of either on hypercalcemia, and no adverse events.

CONCLUSIONS

Results suggest that neither vitamin D nor zinc supplementation improves COVID-19 treatment outcomes in this population. However, much larger-scale evidence, particularly from populations with vitamin D or zinc deficiency and severe infection, is required to corroborate our findings. This trial was registered at ClinicalTrials.gov and the Clinical Trials Registry of India as NCT04641195 and CTRI/2021/04/032593 respectively.

Repurposed drug studies on the primary prevention of SARS-CoV-2 infection during the pandemic: systematic review and meta-analysis

OBJECTIVE

Current evidence on the effectiveness of SARS-CoV-2 prophylaxis is inconclusive. We aimed to systematically evaluate published studies on repurposed drugs for the prevention of laboratory-confirmed SARS-CoV-2 infection and/or COVID-19 among healthy adults.

DESIGN

Systematic review.

ELIGIBILITY

Quantitative experimental and observational intervention studies that evaluated the effectiveness of repurposed drugs for the primary prevention of SARS-CoV-2 infection and/or COVID-19 disease.

DATA SOURCE

PubMed and Embase (1 January 2020-28 September 2022).

RISK OF BIAS

Cochrane Risk of Bias 2.0 and Risk of Bias in Non-Randomised Studies of Interventions tools were applied to assess the quality of studies.

DATA ANALYSIS

Meta-analyses for each eligible drug were performed if ≥2 similar study designs were available.

RESULTS

In all, 65 (25 trials, 40 observational) and 29 publications were eligible for review and meta-analyses, respectively. Most studies pertained to hydroxychloroquine (32), ACE inhibitor (ACEi) or angiotensin receptor blocker (ARB) (11), statin (8), and ivermectin (8). In trials, hydroxychloroquine prophylaxis reduced laboratory-confirmed SARS-CoV-2 infection (risk ratio: 0.82 (95% CI 0.74 to 0.90), I2=48%), a result largely driven by one clinical trial (weight: 60.5%). Such beneficial effects were not observed in observational studies, nor for prognostic clinical outcomes. Ivermectin did not significantly reduce the risk of SARS-CoV-2 infection (RR: 0.35 (95% CI 0.10 to 1.26), I2=96%) and findings for clinical outcomes were inconsistent. Neither ACEi or ARB were beneficial in reducing SARS-CoV-2 infection. Most of the evidence from clinical trials was of moderate quality and of lower quality in observational studies.

CONCLUSIONS

Results from our analysis are insufficient to support an evidence-based repurposed drug policy for SARS-CoV-2 prophylaxis because of inconsistency. In the view of scarce supportive evidence on repurposing drugs for COVID-19, alternative strategies such as immunisation of vulnerable people are warranted to prevent the future waves of infection.

PROSPERO REGISTRATION NUMBER

CRD42021292797.

COVID-19 Excess Deaths in Peru's 25 States in 2020: Nationwide Trends, Confounding Factors, and Correlations With the Extent of Ivermectin Treatment by State

Introduction In 2020, nations hastened to contain an emerging COVID-19 pandemic by deploying diverse public health approaches, but conclusive appraisals of the efficacy of these approaches are elusive in most cases. One of the medicines deployed, ivermectin (IVM), a macrocyclic lactone having biochemical activity against SARS-CoV-2 through competitive binding to its spike protein, has yielded mixed results in randomized clinical trials (RCTs) for COVID-19 treatments. In Peru, an opportunity to track the efficacy of IVM with a close consideration of confounding factors was provided through data for excess deaths as correlated with IVM use in 2020, under semi-autonomous policies in its 25 states. Methods To evaluate possible IVM treatment effects, excess deaths as determined from Peruvian national health data were analyzed by state for ages ≥60 in Peru's 25 states. These data were compared with monthly summary data for excess deaths in Peru for the period 2020-2021 as published by the WHO in 2022. To identify potential confounding factors, Google mobility data, population densities, SARS-CoV-2 genetic variations, and seropositivity rates were also examined. Results Reductions in excess deaths over a period of 30 days after peak deaths averaged 74% in the 10 states with the most intensive IVM use. As determined across all 25 states, these reductions in excess deaths correlated closely with the extent of IVM use (p<0.002). During four months of IVM use in 2020, before a new president of Peru restricted its use, there was a 14-fold reduction in nationwide excess deaths and then a 13-fold increase in the two months following the restriction of IVM use. Notably, these trends in nationwide excess deaths align with WHO summary data for the same period in Peru. Conclusions The natural experiment that was put into motion with the authorization of IVM use for COVID-19 in Peru in May 2020, as analyzed using data on excess deaths by locality and by state from Peruvian national health sources, resulted in strong evidence for the drug's effectiveness. Several potential confounding factors, including effects of a social isolation mandate imposed in May 2020, variations in the genetic makeup of the SARS-CoV-2 virus, and differences in seropositivity rates and population densities across the 25 states, were considered but did not appear to have significantly influenced these outcomes.

Safety and efficacy of hydroxychloroquine as prophylactic against COVID-19 in healthcare workers: a meta-analysis of randomised clinical trials

OBJECTIVE

We studied the safety and efficacy of hydroxychloroquine (HCQ) as pre-exposure prophylaxis for COVID-19 in healthcare workers (HCWs), using a meta-analysis of randomised controlled trials (RCTs).

DATA SOURCES

PubMed and EMBASE databases were searched to identify randomised trials studying HCQ.

STUDY SELECTION

Ten RCTs were identified (n=5079 participants).

DATA EXTRACTION AND SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used in this systematic review and meta-analysis between HCQ and placebo using a Bayesian random-effects model. A pre-hoc statistical analysis plan was written.

MAIN OUTCOMES

The primary efficacy outcome was PCR-confirmed SARS-CoV-2 infection and the primary safety outcome was incidence of adverse events. The secondary outcome included clinically suspected SARS-CoV-2 infection.

RESULTS

Compared with placebo, HCWs randomised to HCQ had no significant difference in PCR-confirmed SARS-CoV-2 infection (OR 0.92, 95% credible interval (CI): 0.58, 1.37) or clinically suspected SARS-CoV-2 infection (OR 0.78, 95% CI: 0.57, 1.10), but significant difference in adverse events (OR 1.35, 95% CI: 1.03, 1.73).

CONCLUSIONS AND RELEVANCE

Our meta-analysis of 10 RCTs investigating the safety and efficacy of HCQ as pre-exposure prophylaxis in HCWs found that compared with placebo, HCQ does not significantly reduce the risk of confirmed or clinically suspected SARS-CoV-2 infection, while HCQ significantly increases adverse events.

PROSPERO REGISTRATION NUMBER

CRD42021285093.

Preprocedural Viral Load Effects of Oral Antiseptics on SARS-CoV-2 in Patients with COVID-19: A Systematic Review

(1) There are limited clinical trials to support the effectiveness of mouth rinses when used as a preprocedural rinse against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This systematic review aims to evaluate the efficacy of antiseptic mouth rinses as a preprocedural rinse in reducing SARS-CoV-2 oral viral load in-vivo. (2) Methods: A literature search was conducted through November 2022 for the following databases: PubMed, Web of Science, Cochrane Library, and Google Scholar. The evaluated outcomes were quantitative changes in viral load and the statistical significance of that change after using antiseptic mouth rinses. (3) Results: 14 randomized controlled trials (RCT) were selected for risk of bias assessment and data extraction. (4) Conclusion: Within the limits of this systematic review, preprocedural mouth rinses may significantly reduce SARS-CoV-2 in the mouth, thus, reducing the viral particles available for airborne dispersion. Preprocedural mouth rinses may be an effective strategy for reducing airborne SARS-CoV-2 dispersion in the environment. Their use may be a preventive strategy to reduce the spread of COVID-19 in selected medical and healthcare facilities, including dental clinics. Potential preprocedural mouth rinses are identified for use as an integral part of safe practice for healthcare protocols. This systematic review was registered with the National Institute for Health Research, international prospective register of systematic reviews (PROSPERO): CRD42022315177.

Ivermectin's Role in the Prevention of COVID-19: A Systematic Review and Meta-Analysis

This systematic review was performed to determine the population that benefited from prophylactic ivermectin. Seven databases of health-related studies were searched for eligible trials without language restrictions. Randomized controlled trials (RCTs) and cohort studies investigating ivermectin for coronavirus disease 2019 (COVID-19) prevention were included. Data were pooled using a random-effects model, and subgroups were analyzed by study type and the pre- or postexposure population. The certainty of the evidence was determined by the Grading of Recommendations Assessment, Development, and Evaluation approach. Furthermore, 4 RCTs and 4 cohort studies with a moderate to high risk of bias were included in the analysis. The prophylactic use of ivermectin significantly decreased the overall incidence of COVID-19 (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.16-0.44). Nevertheless, the positive result was not supported by the RCT. Ivermectin was associated with a lower risk of COVID-19 (OR, 0.22; 95% CI, 0.12-0.40) in the preexposure population, whereas no protective effect was observed in the postexposure population (OR, 0.39; 95% CI, 0.09-1.67). In summary, prophylactic ivermectin did not prevent COVID-19 in the postexposure population. Although the protective effect of ivermectin was shown in the overall and preexposure populations, the results were unreliable owing to poor-quality evidence.

Electrostatic Surface Potential as a Key Parameter in Virus Transmission and Evolution: How to Manage Future Virus Pandemics in the Post-COVID-19 Era

Virus-cell interactions involve fundamental parameters that need to be considered in strategies implemented to control viral outbreaks. Among these, the surface electrostatic potential can give valuable information to deal with new epidemics. In this article, we describe the role of this key parameter in the hemagglutination of red blood cells and in the co-evolution of synaptic receptors and neurotransmitters. We then establish the functional link between lipid rafts and the electrostatic potential of viruses, with special emphasis on gangliosides, which are sialic-acid-containing, electronegatively charged plasma membrane components. We describe the common features of ganglioside binding domains, which include a wide variety of structures with little sequence homology but that possess key amino acids controlling ganglioside recognition. We analyze the role of the electrostatic potential in the transmission and intra-individual evolution of HIV-1 infections, including gatekeeper and co-receptor switch mechanisms. We show how to organize the epidemic surveillance of influenza viruses by focusing on mutations affecting the hemagglutinin surface potential. We demonstrate that the electrostatic surface potential, by modulating spike-ganglioside interactions, controls the hemagglutination properties of coronaviruses (SARS-CoV-1, MERS-CoV, and SARS-CoV-2) as well as the structural dynamics of SARS-CoV-2 evolution. We relate the broad-spectrum antiviral activity of repositioned molecules to their ability to disrupt virus-raft interactions, challenging the old concept that an antibiotic or anti-parasitic cannot also be an antiviral. We propose a new concept based on the analysis of the electrostatic surface potential to develop, in real time, therapeutic and vaccine strategies adapted to each new viral epidemic.

Daily tenofovir disoproxil fumarate/emtricitabine and hydroxychloroquine for pre-exposure prophylaxis of COVID-19: a double-blind placebo-controlled randomized trial in healthcare workers

OBJECTIVES

To assess the effect of hydroxychloroquine (HCQ) and Tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) as pre-exposure prophylaxis on COVID-19 risk.

METHODS

EPICOS is a double-blind, placebo-controlled randomized trial conducted in Spain, Bolivia, and Venezuela. Healthcare workers with negative SARS-CoV-2 IgM/IgG test were randomly assigned to the following: daily TDF/FTC plus HCQ for 12 weeks, TDF/FTC plus HCQ placebo, HCQ plus TDF/FTC placebo, and TDF/FTC placebo plus HCQ placebo. Randomization was performed in groups of four. Primary outcome was laboratory-confirmed, symptomatic COVID-19. We also studied any (symptomatic or asymptomatic) COVID-19. We compared group-specific 14-week risks via differences and ratios with 95% CIs.

RESULTS

Of 1002 individuals screened, 926 (92.4%) were eligible and there were 14 cases of symptomatic COVID-19: 220 were assigned to the TDF/FTC plus HCQ group (3 cases), 231 to the TDF/FTC placebo plus HCQ group (3 cases), 233 to the TDF/FTC plus HCQ placebo group (3 cases), and 223 to the double placebo group (5 cases). Compared with the double placebo group, 14-week risk ratios (95% CI) of symptomatic COVID-19 were 0.39 (0.00-1.98) for TDF + HCQ, 0.34 (0.00-2.06) for TDF, and 0.49 (0.00-2.29) for HCQ. Corresponding risk ratios of any COVID-19 were 0.51 (0.21-1.00) for TDF + HCQ, 0.81 (0.44-1.49) for TDF, and 0.73 (0.41-1.38) for HCQ. Adverse events were generally mild.

DISCUSSION

The target sample size was not met. Our findings are compatible with both benefit and harm of pre-exposure prophylaxis with TDF/FTC and HCQ, alone or in combination, compared with placebo.

The Role of Vitamin C in Human Immunity and Its Treatment Potential Against COVID-19: A Review Article

The outbreak of the COVID-19 pandemic has left clinicians around the world searching for viable prevention and treatment options to use against the virus. The important physiologic properties of vitamin C have been well documented regarding its use by immune cells and its role as an antioxidant. It has previously shown potential as a prophylactic and treatment option for other respiratory viruses, and because of this, there has been intrigue into whether these positive outcomes translate into a cost-effective prevention and treatment option for COVID-19. To this point, there have only been a few clinical trials performed to assess the validity of this notion, with very few showing definitive positive outcomes when vitamin C has been incorporated into prophylactic or treatment protocols to use against coronavirus. When being used to specifically treat the severe complications that arise from COVID-19, vitamin C is a reliable option to treat COVID-19-induced sepsis but not pneumonia or acute respiratory distress syndrome (ARDS). As a treatment option, high-dose therapy has shown flashes of promise in a few studies although investigators in these studies often subject the testing group to multimodal therapies that include vitamin C as opposed to just vitamin C alone. Given the role that vitamin C has shown to uphold regarding the human immune response, it is currently advised for all individuals to maintain a normal physiologic range of plasma vitamin C through diet or supplements for adequate prophylactic protection against the virus. More research with definitive outcomes will be needed before it is recommended to provide high-dose vitamin C therapy to prevent or treat COVID-19.

Vitamins, microelements and the immune system: current standpoint in the fight against coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) is an acute respiratory disease associated with severe systemic inflammation. The optimal status of vitamins and microelements is considered crucial for the proper functioning of the immune system and necessary for successful recovery. Most patients with respiratory distress in COVID-19 are vitamin and microelement deficient, with vitamin D and Se deficiency being the most common. Anyway, various micronutrient supplements are widely and arbitrarily used for prevention or in the treatment of COVID-19. We aimed to summarise current knowledge about molecular and physiological mechanisms of vitamins (D, A, C, B₆, B₉ and B₁₂) and microelements (Se, Zn, Cu and Fe) involved in the immune system regulation in consideration with COVID-19 pathogenesis, as well as recent findings related to their usage and effects in the prevention and treatment of COVID-19. In the early course of the pandemic, several, mainly observational, studies reported an association of some micronutrients, such as vitamin C, D and Zn, with severity reduction and survival improvement. Still, emerging randomised controlled trials showed no effect of vitamin D on hospitalisation length and no effect of vitamin C and Zn on symptom reduction. Up to date, there is evidence neither for nor against the use of micronutrients in the treatment of COVID-19. The doses that exceed the recommended for the general population and age group should not be used, except in clinical trials. Benefits of supplementation are primarily expected in populations prone to micronutrient deficiencies, who are, as well, at a higher risk of worse outcomes in COVID-19.

Repurposing povidone-iodine to reduce the risk of SARS-CoV-2 infection and transmission: a narrative review

BACKGROUND

Accumulating data suggest antiviral effects of povidone-iodine against the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. This narrative review aims to examine the antiviral mechanisms of povidone-iodine, efficacy of povidone-iodine against the SARS-CoV-2 virus, and safety of povidone-iodine to human epithelial cells and thyroid function.

METHODS

We searched the electronic databases PubMed, Embase, Cochrane Library, ClinicalTrials.gov and World Health Organization's International Clinical Trials Registry Platform for articles containing the keywords "povidone-iodine", "SARS-CoV-2" and "COVID-19" from database inception till 3 June 2021.

RESULTS

Despite in vitro data supporting the anti-SARS-CoV-2 effects of povidone-iodine, findings from clinical studies revealed differences in treatment response depending on study settings (healthy vs. hospitalized individuals), treatment target (nasal vs. oral vs. pharynx), method of administration (oral rinse vs. gargle vs. throat spray) and choice of samples used to measure study endpoints (nasopharyngeal vs. saliva). One large-scale clinical trial demonstrated reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak. Povidone-iodine is also used to disinfect the oro-pharyngeal space prior to dental or otolaryngology procedures. Although existing data suggest minimal impact of povidone-iodine on thyroid function, high-quality safety data are presently lacking.

CONCLUSIONS

Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.Key messagesAccumulating data suggest antiviral effects of povidone-iodine against the SARS-CoV-2 virus.Findings from clinical studies reveal differences in treatment response depending on study settings, treatment target, method of administration and choice of samples used to measure study endpoints. One large-scale clinical trial observed reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak.Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.

Stable thyroid function despite regular use of povidone-iodine throat spray for SARS-CoV-2 prophylaxis

BACKGROUND

It is unclear whether unintentional ingestion of povidone-iodine following its application to the oropharyngeal space could affect thyroid function.

OBJECTIVE

To examine thyroid function among individuals who regularly apply povidone-iodine throat spray for SARS-CoV-2 prophylaxis.

METHODS

We designed a case-control study to compare thyroid function among participants who received povidone-iodine throat spray three times a day for 42 days ('cases') and those who received vitamin C ('controls'). Thyroid function was assessed by profiling serum TSH, free T3, and free T4; iodine status was estimated using serum thyroglobulin level, while infection status was determined by measuring anti-SARS-CoV-2 antibody against the nucleocapsid antigen. All measurements were performed in pairs, at baseline and 42 days later. Pre-post changes in thyroid function were compared between groups, before and after stratification according to baseline TSH quartiles.

RESULTS

A total of 177 men (117 cases and 60 controls) (mean age, 32.2 years) were included. Despite comparable demographics and clinical profiles, no clinically or statistically significant differences were observed in thyroid indices between 'cases' and 'controls' before and after stratification according to TSH quartiles. None of the participants developed symptomatic hypo- or hyperthyroidism throughout the study. Post-hoc analysis did not reveal differences in thyroid function according to infection status.

CONCLUSIONS

Data from this study support the overall safety of povidone-iodine use in the oropharyngeal space for SARS-CoV-2 prophylaxis among individuals with normal thyroid function and subclinical thyroid disease.

A prospective, randomized, open-label trial of early versus late povidone-iodine gargling in patients with COVID-19

Povidone-iodine (PVP-I) is a broad-spectrum antiseptic reagent that has been used for over 50 years. The purpose of this study is to look into the effect of gargling with PVP-I gargling on virus clearance and saliva infectivity in COVID-19. A prospective, randomized, open-label trial of intervention with PVP-I was conducted at three quarantine facilities in Osaka, Japan, enrolling adolescents and adults with asymptomatic-to-mild COVID-19. Patients were randomly allocated to the early and late intervention group at a 1:1 ratio. The early group gargled with PVP-I from days 2 to day 6; the late group gargled with water first, then with PVP-I from day 5 after sampling till day 6. The primary and secondary endpoints were viral clearance for SARS-CoV-2 using RT-qPCR at days 5 and 6, respectively, and the investigational endpoint was saliva infectivity clearance on day5. We enrolled 430 participants, with 215 assigned to each group, and 139 in the early group and 140 in the late had a positive saliva RT-qPCR test on day 2. On day 5, the early group had a significantly higher RT-qPCR negative rate than that of the late group (p = 0.015), and the early had a significantly higher clearance rate of infectivity (p = 0.025). During the PVP-I intervention, one participant reported oropharyngeal discomfort. Gargling with PVP-I may hasten virus clearance and reduce viral transmission via salivary droplets and aerosols in patients with asymptomatic-to-mild COVID-19. (Clinical trial registration numbers: jRCT1051200078 and dateof registration: 24/11/2020).

A study of impurities in the repurposed COVID-19 drug hydroxychloroquine sulfate using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry and liquid chromatography-solid-phase extraction-nuclear magnetic resonance

RATIONALE

Hydroxychloroquine sulfate is effective in the treatment of malaria and autoimmune diseases and as an antiviral drug. However, unreported impurities are often detected in this drug, which pose a health risk. In this study, the structures of hydroxychloroquine and six unknown impurities were analyzed using ultra-high-performance liquid chromatography-quadrupole/time-of-flight-tandem mass spectrometry (UHPLC-Q/TOF/MS/MS), and the structures were characterized using liquid chromatography-solid-phase extraction-nuclear magnetic resonance (LC-SPE-NMR) spectroscopy.

METHODS

An Agilent InfinityLad Poroshell HPH-C18 column (100 × 4.6 mm, 2.7 μm) was used. For the analysis of hydroxychloroquine and six unknown impurities, the mobile phase was 20 mM ammonium formate aqueous solution and methanol/acetonitrile (80:20, v/v) using gradient elution. Full-scan MS and MS² were performed to obtain as much structural information as possible. In addition, six unknown impurities were separated by semi-preparative liquid chromatography and characterized using LC-SPE-NMR.

RESULTS

The MS² fragmentation patterns of the impurities were investigated, leading to more structural information and an understanding of the fragmentation pathways of the impurities. The structures of the unknown impurities were confirmed using NMR. In addition, some possible pathways of the formation of the impurities in the drugs were outlined, and these impurities were found to be process impurities.

CONCLUSIONS

Based on the identification and characterization of these impurities, this study also describes the cause of the production of the impurities and provides insights for companies to improve their production processes and a scientific basis for the improvement of the related pharmacopoeias.

The Mechanisms of Zinc Action as a Potent Anti-Viral Agent: The Clinical Therapeutic Implication in COVID-19

The pandemic of COVID-19 was caused by a novel coronavirus termed as SARS-CoV2 and is still ongoing with high morbidity and mortality rates in the whole world. The pathogenesis of COVID-19 is highly linked with over-active immune and inflammatory responses, leading to activated cytokine storm, which contribute to ARDS with worsen outcome. Currently, there is no effective therapeutic drug for the treatment of COVID-19. Zinc is known to act as an immune modulator, which plays an important role in immune defense system. Recently, zinc has been widely considered as an anti-inflammatory and anti-oxidant agent. Accumulating numbers of studies have revealed that zinc plays an important role in antiviral immunity in several viral infections. Several early clinical trials clearly indicate that zinc treatment remarkably decreased the severity of the upper respiratory infection of rhinovirus in humans. Currently, zinc has been used for the therapeutic intervention of COVID-19 in many different clinical trials. Several clinical studies reveal that zinc treatment using a combination of HCQ and zinc pronouncedly reduced symptom score and the rates of hospital admission and mortality in COVID-19 patients. These data support that zinc might act as an anti-viral agent in the addition to its anti-inflammatory and anti-oxidant properties for the adjuvant therapeutic intervention of COVID-19.

Zinc and COVID-19: Immunity, Susceptibility, Severity and Intervention

During the coronavirus disease 2019 (COVID-19) pandemic and continuing emergence of viral mutants, there has been a lack of effective treatment methods. Zinc maintains immune function, with direct and indirect antiviral activities. Zinc nutritional status is a critical factor in antiviral immune responses. Importantly, COVID-19 and zinc deficiency overlap in high-risk population. Hence, the potential effect of zinc as a preventive and adjunct therapy for COVID-19 is intriguing. Here, this review summarizes the immune and antiviral function of zinc, the relationship between zinc levels, susceptibility, and severity of COVID-19, and the effect of zinc supplementation on COVID-19. Existing studies have confirmed that zinc deficiency was associated with COVID-19 susceptibility and severity. Zinc supplementation plays a potentially protective role in enhancing immunity, decreasing susceptibility, shortening illness duration, and reducing the severity of COVID-19. We recommend that zinc levels should be monitored, particularly in COVID-19 patients, and zinc as a preventive and adjunct therapy for COVID-19 should be considered for groups at risk of zinc deficiency to reduce susceptibility and disease severity.

Systematic review and meta-analysis of randomized trials of hydroxychloroquine for the prevention of COVID-19

BACKGROUND

Recruitment into randomized trials of hydroxychloroquine (HCQ) for prevention of COVID-19 has been adversely affected by a widespread conviction that HCQ is not effective for prevention. In the absence of an updated systematic review, we conducted a meta-analysis of randomized trials that study the effectiveness of HCQ to prevent COVID-19.

METHODS

A search of PubMed, medRxiv, and clinicaltrials.gov combined with expert consultation found 11 completed randomized trials: 7 pre-exposure prophylaxis trials and 4 post-exposure prophylaxis trials. We obtained or calculated the risk ratio of COVID-19 diagnosis for assignment to HCQ versus no HCQ (either placebo or usual care) for each trial, and then pooled the risk ratio estimates.

RESULTS

The pooled risk ratio estimate of the pre-exposure prophylaxis trials was 0.72 (95% CI: 0.58-0.90) when using either a fixed effect or a standard random effects approach, and 0.72 (95% CI: 0.55-0.95) when using a conservative modification of the Hartung-Knapp random effects approach. The corresponding estimates for the post-exposure prophylaxis trials were 0.91 (95% CI: 0.72-1.16) and 0.91 (95% CI: 0.62-1.35). All trials found a similar rate of serious adverse effects in the HCQ and no HCQ groups.

DISCUSSION

A benefit of HCQ as prophylaxis for COVID-19 cannot be ruled out based on the available evidence from randomized trials. However, the "not statistically significant" findings from early prophylaxis trials were widely interpreted as definite evidence of lack of effectiveness of HCQ. This interpretation disrupted the timely completion of the remaining trials and thus the generation of precise estimates for pandemic management before the development of vaccines.

Systematic review and meta-analysis of ivermectin for treatment of COVID-19: evidence beyond the hype

BACKGROUND

The role of ivermectin in the treatment of COVID-19 is still under debate, yet the drug has been widely used in some parts of the world, as shown by impressive market data. The available body of evidence may have changed over the last months, as studies have been retracted and "standards of care" (SOC) used in control groups have changed with rapidly evolving knowledge on COVID-19. This review aims to summarize and critically appraise the evidence of randomized controlled trials (RCTs) of ivermectin, assessing clinical outcomes in COVID-19 patients.

METHODS

RCTs evaluating the effects of ivermectin in adult patients with COVID-19 were searched through June 22, 2022, in four databases, L.OVE platform, clinical trial registries and pre-prints platforms. Primary endpoints included all-cause mortality and invasive ventilation requirement. Secondary endpoint was the occurrence of adverse events. Risk of bias was evaluated using the Cochrane Risk of Bias 2.0 tool. Meta-analysis included only studies which compared ivermectin to placebo or SOC. Random-effects were used to pool the risk ratios (RRs) of individual trials. The quality of evidence was evaluated using GRADE. The protocol was register in PROSPERO (CRD42021257471).

RESULTS

Twenty-five RCTs fulfilled inclusion criteria (n = 6310). Of those, 14 compared ivermectin with placebo, in night ivermectin associated with SOC was compared to SOC and two studies compared ivermectin to an active comparator. Most RCTs had some concerns or high risk of bias, mostly due to lack of concealment of the randomization sequence and allocation, lack of blinding and high number of missing cases. Ivermectin did not show an effect in reducing mortality (RR = 0.76; 95%CI: 0.52-1.11) or mechanical ventilation (RR = 0.74; 95%CI: 0.48-1.16). This effect was consistent when comparing ivermectin vs. placebo, and ivermectin associated with SOC vs. SOC, as well as in sensitivity analysis. Additionally, there was very low quality of evidence regarding adverse effects (RR = 1.07; 95%CI: 0.84-1.35).

CONCLUSIONS

The evidence suggests that ivermectin does not reduce mortality risk and the risk of mechanical ventilation requirement. Although we did not observe an increase in the risk of adverse effects, the evidence is very uncertain regarding this endpoint.

Estimating transmission dynamics of SARS-CoV-2 at different intraspatial levels in an institutional outbreak

Introduction

Large, localised outbreaks of COVID-19 have been repeatedly reported in high-density residential institutions. Understanding the transmission dynamics will inform outbreak response and the design of living environments that are more resilient to future outbreaks.

Methods

We developed an individual-based, multilevel transmission dynamics model using case, serology and symptom data from a 60-day cluster randomised trial of prophylaxes in a densely populated foreign worker dormitory in Singapore. Using Bayesian data augmentation, we estimated the basic reproduction number and the contribution that within-room, between-level and across-block transmission made to it, and the prevalence of infection over the study period across different spatial levels. We then simulated the impact of changing the building layouts in terms of floors and blocks on outbreak size.

Results

We found that the basic reproduction number was 2.76 averaged over the different putative prophylaxes, with substantial contributions due to transmission beyond the residents’ rooms. By the end of ~60 days of follow up, prevalence was 64.4 % (95 % credible interval 64.2–64.6 %). Future outbreak sizes could feasibly be halved by reducing the density to include additional housing blocks, or taller buildings, while retaining the overall number of men in the complex.

Discussion

The methods discussed can potentially be utilised to estimate transmission dynamics at any high-density accommodation site with the availability of case and serology data. The restructuring of infrastructure to reduce the number of residents per room can dramatically slow down epidemics, and therefore should be considered by policymakers as a long-term intervention.

Microbiome-Based Hypothesis on Ivermectin's Mechanism in COVID-19: Ivermectin Feeds Bifidobacteria to Boost Immunity

Ivermectin is an anti-parasitic agent that has gained attention as a potential COVID-19 therapeutic. It is a compound of the type Avermectin, which is a fermented by-product of Streptomyces avermitilis. Bifidobacterium is a member of the same phylum as Streptomyces spp., suggesting it may have a symbiotic relation with Streptomyces. Decreased Bifidobacterium levels are observed in COVID-19 susceptibility states, including old age, autoimmune disorder, and obesity. We hypothesize that Ivermectin, as a by-product of Streptomyces fermentation, is capable of feeding Bifidobacterium, thereby possibly preventing against COVID-19 susceptibilities. Moreover, Bifidobacterium may be capable of boosting natural immunity, offering more direct COVID-19 protection. These data concord with our study, as well as others, that show Ivermectin protects against COVID-19.

Antiparasitic Drugs against SARS-CoV-2: A Comprehensive Literature Survey

More than two years have passed since the viral outbreak that led to the novel infectious respiratory disease COVID-19, caused by the SARS-CoV-2 coronavirus. Since then, the urgency for effective treatments resulted in unprecedented efforts to develop new vaccines and to accelerate the drug discovery pipeline, mainly through the repurposing of well-known compounds with broad antiviral effects. In particular, antiparasitic drugs historically used against human infections due to protozoa or helminth parasites have entered the main stage as a miracle cure in the fight against SARS-CoV-2. Despite having demonstrated promising anti-SARS-CoV-2 activities in vitro, conflicting results have made their translation into clinical practice more difficult than expected. Since many studies involving antiparasitic drugs are currently under investigation, the window of opportunity might be not closed yet. Here, we will review the (controversial) journey of these old antiparasitic drugs to combat the human infection caused by the novel coronavirus SARS-CoV-2.

Ivermectin for preventing and treating COVID-19

BACKGROUND

Ivermectin, an antiparasitic agent, inhibits the replication of viruses in vitro. The molecular hypothesis of ivermectin's antiviral mode of action suggests an inhibitory effect on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in early stages of infection. Currently, evidence on ivermectin for prevention of SARS-CoV-2 infection and COVID-19 treatment is conflicting.

OBJECTIVES

To assess the efficacy and safety of ivermectin plus standard of care compared to standard of care plus/minus placebo, or any other proven intervention for people with COVID-19 receiving treatment as inpatients or outpatients, and for prevention of an infection with SARS-CoV-2 (postexposure prophylaxis).

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register, Web of Science (Emerging Citation Index and Science Citation Index), WHO COVID-19 Global literature on coronavirus disease, and HTA database weekly to identify completed and ongoing trials without language restrictions to 16 December 2021. Additionally, we included trials with > 1000 participants up to April 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing ivermectin to standard of care, placebo, or another proven intervention for treatment of people with confirmed COVID-19 diagnosis, irrespective of disease severity or treatment setting, and for prevention of SARS-CoV-2 infection. Co-interventions had to be the same in both study arms.  For this review update, we reappraised eligible trials for research integrity: only RCTs prospectively registered in a trial registry according to WHO guidelines for clinical trial registration were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

We assessed RCTs for bias, using the Cochrane RoB 2 tool. We used GRADE to rate the certainty of evidence for outcomes in the following settings and populations: 1) to treat inpatients with moderate-to-severe COVID-19, 2) to treat outpatients with mild COVID-19 (outcomes: mortality, clinical worsening or improvement, (serious) adverse events, quality of life, and viral clearance), and 3) to prevent SARS-CoV-2 infection (outcomes: SARS-CoV-2 infection, development of COVID-19 symptoms, admission to hospital, mortality, adverse events and quality of life).

MAIN RESULTS

We excluded seven of the 14 trials included in the previous review version; six were not prospectively registered and one was non-randomized. This updated review includes 11 trials with 3409 participants investigating ivermectin plus standard of care compared to standard of care plus/minus placebo. No trial investigated ivermectin for prevention of infection or compared ivermectin to an intervention with proven efficacy. Five trials treated participants with moderate COVID-19 (inpatient settings); six treated mild COVID-19 (outpatient settings). Eight trials were double-blind and placebo-controlled, and three were open-label. We assessed around 50% of the trial results as low risk of bias. We identified 31 ongoing trials. In addition, there are 28 potentially eligible trials without publication of results, or with disparities in the reporting of the methods and results, held in 'awaiting classification' until the trial authors clarify questions upon request. Ivermectin for treating COVID-19 in inpatient settings with moderate-to-severe disease We are uncertain whether ivermectin plus standard of care compared to standard of care plus/minus placebo reduces or increases all-cause mortality at 28 days (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.14 to 2.51; 3 trials, 230 participants; very low-certainty evidence); or clinical worsening, assessed by participants with new need for invasive mechanical ventilation or death at day 28 (RR 0.82, 95% CI 0.33 to 2.04; 2 trials, 118 participants; very low-certainty evidence); or serious adverse events during the trial period (RR 1.55, 95% CI 0.07 to 35.89; 2 trials, 197 participants; very low-certainty evidence). Ivermectin plus standard of care compared to standard of care plus placebo may have little or no effect on clinical improvement, assessed by the number of participants discharged alive at day 28 (RR 1.03, 95% CI 0.78 to 1.35; 1 trial, 73 participants; low-certainty evidence); on any adverse events during the trial period (RR 1.04, 95% CI 0.61 to 1.79; 3 trials, 228 participants; low-certainty evidence); and on viral clearance at 7 days (RR 1.12, 95% CI 0.80 to 1.58; 3 trials, 231 participants; low-certainty evidence). No trial investigated quality of life at any time point. Ivermectin for treating COVID-19 in outpatient settings with asymptomatic or mild disease Ivermectin plus standard of care compared to standard of care plus/minus placebo probably has little or no effect on all-cause mortality at day 28 (RR 0.77, 95% CI 0.47 to 1.25; 6 trials, 2860 participants; moderate-certainty evidence) and little or no effect on quality of life, measured with the PROMIS Global-10 scale (physical component mean difference (MD) 0.00, 95% CI -0.98 to 0.98; and mental component MD 0.00, 95% CI -1.08 to 1.08; 1358 participants; high-certainty evidence). Ivermectin may have little or no effect on clinical worsening, assessed by admission to hospital or death within 28 days (RR 1.09, 95% CI 0.20 to 6.02; 2 trials, 590 participants; low-certainty evidence); on clinical improvement, assessed by the number of participants with all initial symptoms resolved up to 14 days (RR 0.90, 95% CI 0.60 to 1.36; 2 trials, 478 participants; low-certainty evidence); on serious adverse events (RR 2.27, 95% CI 0.62 to 8.31; 5 trials, 1502 participants; low-certainty evidence); on any adverse events during the trial period (RR 1.24, 95% CI 0.87 to 1.76; 5 trials, 1502 participants; low-certainty evidence); and on viral clearance at day 7 compared to placebo (RR 1.01, 95% CI 0.69 to 1.48; 2 trials, 331 participants; low-certainty evidence). None of the trials reporting duration of symptoms were eligible for meta-analysis.

AUTHORS' CONCLUSIONS

For outpatients, there is currently low- to high-certainty evidence that ivermectin has no beneficial effect for people with COVID-19. Based on the very low-certainty evidence for inpatients, we are still uncertain whether ivermectin prevents death or clinical worsening or increases serious adverse events, while there is low-certainty evidence that it has no beneficial effect regarding clinical improvement, viral clearance and adverse events. No evidence is available on ivermectin to prevent SARS-CoV-2 infection. In this update, certainty of evidence increased through higher quality trials including more participants. According to this review's living approach, we will continually update our search.

A review of the effects of ATP and hydroxychloroquine on the phase separation of the SARS-CoV-2 nucleocapsid protein

SARS-CoV-2 is the coronavirus causing the ongoing pandemic with > 460 millions of infections and > 6 millions of deaths. SARS-CoV-2 nucleocapsid (N) is the only structural protein which plays essential roles in almost all key steps of the viral life cycle with its diverse functions depending on liquid-liquid phase separation (LLPS) driven by interacting with various nucleic acids. The 419-residue N protein is highly conserved in all variants including delta and omicron, and composed of both folded N-/C-terminal domains (NTD/CTD) as well as three long intrinsically disordered regions (IDRs). Recent results have suggested that its CTD and IDRs are also cryptic nucleic acid-binding domains. In this context, any small molecules capable of interfering in its interaction with nucleic acids are anticipated to modulate its LLPS and associated functions. Indeed, ATP, the energy currency existing at very high concentrations (2-12 mM) in all living cells but absent in viruses, modulates LLPS of N protein, and consequently appears to be evolutionarily hijacked by SARS-CoV-2 to promote its life cycle. Hydroxychloroquine (HCQ) has been also shown to specifically bind NTD and CTD to inhibit their interactions with nucleic acids, as well as to disrupt LLPS. Particularly, the unique structure of the HCQ-CTD complex offers a promising strategy for further design of anti-SARS-CoV-2 drugs with better affinity and specificity. The finding may indicate that LLPS is indeed druggable by small molecules, thus opening up a promising direction for drug discovery/design by targeting LLPS in general.

Hydroxychloroquine plus personal protective equipment versus personal protective equipment alone for the prevention of laboratory-confirmed COVID-19 infections among healthcare workers: a multicentre, parallel-group randomised controlled trial from India

OBJECTIVES

To determine whether hydroxychloroquine when used with personal protective equipment reduces the proportion of laboratory-confirmed COVID-19 among healthcare workers in comparison to the use of personal protective equipment alone.

DESIGN

Multicentre, parallel-group, open-label randomised trial. Enrolment started on 29 June 2020 and stopped on 4 February 2021. Participants randomised in HydrOxychloroquine Prophylaxis Evaluation were followed for 6 months.

SETTING

9 hospitals across India.

PARTICIPANTS

Healthcare workers in an environment with exposure to COVID-19 were randomised in a 1:1 ratio to hydroxychloroquine plus use of personal protective equipment or personal protective equipment alone. 886 participants were screened and 416 randomised (213 hydroxychloroquine arm and 203 personal protective equipment).

INTERVENTION

Participants in intervention arm received 800 mg of hydroxychloroquine on day of randomisation and then 400 mg once a week for 12 weeks in addition to the use of personal protective equipment. In the control arm, participants continued to use personal protective equipment alone.

MAIN OUTCOME

Proportion of laboratory-confirmed COVID-19 in the 6 months after randomisation.

RESULTS

Participants were young (mean age 32.1 years, SD 9.1 years) with low-comorbid burden. 47.4% were female. In the 6 months after randomisation (primary analysis population=413), 11 participants assigned to the hydroxychloroquine group and 12 participants assigned to the standard practice group met the primary endpoint (5.2% vs 5.9%; OR 0.85, 95% CI 0.35 to 2.07, p=0.72). There was no heterogeneity of treatment effect in any prespecified subgroup. There were no significant differences in the secondary outcomes. The adverse event rates were 9.9% and 6.9% in the hydroxychloroquine and standard practice arms, respectively. There were no serious adverse events in either group.

CONCLUSIONS AND RELEVANCE

Hydroxychloroquine along with personal protective equipment was not superior to personal protective equipment alone on the proportion of laboratory-confirmed COVID-19. Definitive conclusions are precluded as the trial stopped early for futility, and hence was underpowered.

TRIAL REGISTRATION NUMBER

CTRI/2020/05/025067.

Pharmacometric and Electrocardiographic Evaluation of Chloroquine and Azithromycin in Healthy Volunteers

Chloroquine and azithromycin were developed in combination for the preventive treatment of malaria in pregnancy, and more recently were proposed as coronavirus disease 2019 (COVID‐19) treatment options. Billions of doses of chloroquine have been administered worldwide over the past 70 years but concerns regarding cardiotoxicity, notably the risk of torsades de pointes (TdP), remain. This investigation aimed to characterize the pharmacokinetics and electrocardiographic effects of chloroquine and azithromycin observed in a large previously conducted healthy volunteer study. Healthy adult volunteers (n = 119) were randomized into 5 arms: placebo, chloroquine alone (600 mg base), or chloroquine with either 500 mg, 1,000 mg, or 1,500 mg of azithromycin all given daily for 3 days. Chloroquine and azithromycin levels, measured using liquid‐chromatography tandem mass spectrometry, and electrocardiograph intervals were recorded at frequent intervals. Time‐matched changes in the PR, QRS, and heart rate‐corrected JT, and QT intervals were calculated and the relationship with plasma concentrations was evaluated using linear and nonlinear mixed‐effects modeling. Chloroquine and azithromycin pharmacokinetics were described satisfactorily by two‐ and three‐compartment distribution models, respectively. No drug–drug interaction between chloroquine and azithromycin was observed. Chloroquine resulted in concentration‐dependent prolongation of the PR, QRS, JTc and QTc intervals with a minimal additional effect of azithromycin. QRS widening contributed ~ 28% of the observed QT prolongation. Chloroquine causes significant concentration‐dependent delays in both ventricular depolarization and repolarization. Co‐administration of azithromycin did not significantly increase these effects. The arrhythmogenic risk of TdP associated with chloroquine may have been substantially overestimated in studies which did not separate electrocardiograph QRS and JT prolongation.

Antimicrobials in COVID-19: strategies for treating a COVID-19 pandemic

The COVID-19 pandemic continues to pose a serious global challenge, with the world engulfed in fighting second, third and fourth waves of the disease, which is reaching scary proportions in terms of cases and mortality in countries like India. Despite the urgent need of proven management protocols, there is still confusion about the best practices for treating COVID-19 with different pharmaceutical interventions. Antimicrobials are empirically used in COVID-19 patients. During the initial phase of this pandemic, hydroxychloroquine, ivermectin, azithromycin and doxycycline were widely suggested for possible prophylaxis or treatment for COVID-19 in outpatient as well as hospitalized settings. Various national and international guidelines recommended its use. However, cumulative evidence from subsequent clinical trials has revealed no significant clinical benefits in any setting, with the risk of adverse effects being high particularly in combination with azithromycin. Yet, there is continued use of antimicrobials particularly in outpatient settings which should be avoided because there is no justifiable rationale for doing so. Antimicrobial resistance (AMR) was one of the top problems for global public health before the coronavirus 2019 (COVID-19) pandemic began. AMR, which is already a difficult problem, must now be handled in the context of a changing healthcare sector.

Ivermectin for the prevention of COVID-19: addressing potential bias and medical fraud

BACKGROUND

Ivermectin is an antiparasitic drug being investigated in clinical trials for the prevention of COVID-19. However, there are concerns about the quality of some of these trials.

OBJECTIVES

To conduct a meta-analysis with randomized controlled trials of ivermectin for the prevention of COVID-19, while controlling for the quality of data. The primary outcome was RT-PCR-confirmed COVID-19 infection. The secondary outcome was rate of symptomatic COVID-19 infection.

METHODS

We conducted a subgroup analysis based on the quality of randomized controlled trials evaluating ivermectin for the prevention of COVID-19. Quality was assessed using the Cochrane risk of bias measures (RoB 2) and additional checks on raw data, where possible.

RESULTS

Four studies were included in the meta-analysis. One was rated as being potentially fraudulent, two as having a high risk of bias and one as having some concerns for bias. Ivermectin did not have a significant effect on preventing RT-PCR-confirmed COVID-19 infection. Ivermectin had a significant effect on preventing symptomatic COVID-19 infection in one trial with some concerns of bias, but this result was based on post hoc analysis of a multi-arm study.

CONCLUSIONS

In this meta-analysis, the use of ivermectin was not associated with the prevention of RT-PCR-confirmed or symptomatic COVID-19. The currently available randomized trials evaluating ivermectin for the prevention of COVID-19 are insufficient and of poor quality.

Bias as a source of inconsistency in ivermectin trials for COVID-19: A systematic review. Ivermectin's suggested benefits are mainly based on potentially biased results

OBJECTIVE

The objective of this systematic review is to summarize the effects of ivermectin for the prevention and treatment of patients with COVID-19 and to assess inconsistencies in results from individual studies with focus on risk of bias due to methodological limitations.

METHODS

We searched the L.OVE platform through July 6, 2021 and included randomized trials (RCTs) comparing ivermectin to standard or other active treatments. We conducted random-effects pairwise meta-analysis, assessed the certainty of evidence using the GRADE approach and performed sensitivity analysis excluding trials with risk of bias.

RESULTS

We included 29 RCTs which enrolled 5592 cases. Overall, the certainty of the evidence was very low to low suggesting that ivermectin may result in important benefits. However, after excluding trials classified as "high risk" or "some concerns" in the risk of bias assessment, most estimates of effect changed substantially: Compared to standard of care, low certainty evidence suggests that ivermectin may not reduce mortality (RD 7 fewer per 1000) nor mechanical ventilation (RD 6 more per 1000), and moderate certainty evidence shows that it probably does not increase symptom resolution or improvement (RD 14 more per 1000) nor viral clearance (RD 12 fewer per 1000).

CONCLUSION

Ivermectin may not improve clinically important outcomes in patients with COVID-19 and its effects as a prophylactic intervention in exposed individuals are uncertain. Previous reports concluding important benefits associated with ivermectin are based on potentially biased results reported by studies with substantial methodological limitations. Further research is needed.

Maoto, a traditional herbal medicine, for post-exposure prophylaxis for Japanese healthcare workers exposed to COVID-19: A single center study

Background

Little research has been done on post-exposure prophylaxis (PEP) for COVID-19. This study was done to determine if maoto, a traditional herbal medicine commonly used for diseases with symptoms similar to those of COVID-19, can be repurposed for post-exposure prophylaxis to prevent the spread of nosocomial infection with SARS-CoV-2.

Methods

A cohort analysis was done of the data of 55 health care workers (HCWs) whether to get infected with SARS-CoV-2 in a Japanese hospital experiencing a COVID-19 cluster in April of 2021. Of these subjects, maoto granules for medical use were prescribed for PEP to 42 HCWs and taken for three days in mid-April. Controls were 13 HCWs who rejected the use of maoto. Polymerase chain reaction was performed routinely once or twice a week or when a participant presented with symptoms of COVID-19.

Result

There were no background differences between the maoto and control groups by profession, sex, or mean age. No severe adverse reactions were observed. During the observation period of 1 week, significantly fewer subjects were diagnosed with COVID-19 in the maoto group (N = 3, 7.1%) than in the control group (N = 6, 46.2%). The prophylactic effectiveness of maoto was 84.5%.

Conclusion

Oral administration of maoto is suggested to be effective as PEP against nosocomial COVID-19 infection.

Ivermectin and the Integrity of Healthcare Evidence During COVID-19

The COVID-19 pandemic has been characterized by a lack of clear evidence to guide healthcare professionals, the public and policymakers. The resulting uncertainty, coupled with changing guidelines as additional evidence became available, added to the stress and anxiety reported by decision-makers. Research results are key to providing evidence to guide healthcare decisions. Important questions have arisen about whether various interventions are safe and effective. The evidence found guides those making treatment decisions, and influences those selecting interventions for further evaluation in research studies. As the COVID-19 pandemic intensified, the effectiveness and safety of many pharmaceuticals was queried. Ivermectin will be used to explore the ethics of how healthcare evidence must be critically appraised, even, or especially, during a pandemic. This drug is alleged to be effective in treating COVID-19, with various studies and systematic reviews finding supportive evidence. Some of these have now been linked to concerns about fraud or poor research reporting. This article will focus on the scientific literature and how apparently fraudulent studies were published and influenced treatment decisions, on-going research and public health guidelines. Research evidence is critical during emergencies like pandemics, but urgency should not overtake ethical responsibilities to critically appraise (or evaluate) studies as they become available. These responsibilities apply in various ways to editors, peer-reviewers, news media reporters, and those making treatment decisions, including clinicians, policymakers and the general public. While research article authors have the primary ethical responsibility to reject fraudulent or inaccurate claims, the readers of health research must carefully evaluate all publications. To detect and reject fraudulent healthcare claims, readers need critical appraisal skills that match their level of engagement with those articles. The core principles of critical appraisal will be described in the article, and how they can be adapted for different types of readers. Exemplar tools that develop critical appraisal skills will be noted, with reviews of ivermectin's efficacy explored as examples. As stakeholders in healthcare evidence are increasingly able to identify well-conducted and ethical research they will simultaneously be able to spot and reject fraudulent reports and prevent them from influencing healthcare decisions.

A Deadly Embrace: Hemagglutination Mediated by SARS-CoV-2 Spike Protein at Its 22 N-Glycosylation Sites, Red Blood Cell Surface Sialoglycoproteins, and Antibody

Rouleaux (stacked clumps) of red blood cells (RBCs) observed in the blood of COVID-19 patients in three studies call attention to the properties of several enveloped virus strains dating back to seminal findings of the 1940s. For COVID-19, key such properties are: (1) SARS-CoV-2 binds to RBCs in vitro and also in the blood of COVID-19 patients; (2) although ACE2 is its target for viral fusion and replication, SARS-CoV-2 initially attaches to sialic acid (SA) terminal moieties on host cell membranes via glycans on its spike protein; (3) certain enveloped viruses express hemagglutinin esterase (HE), an enzyme that releases these glycan-mediated bindings to host cells, which is expressed among betacoronaviruses in the common cold strains but not the virulent strains, SARS-CoV, SARS-CoV-2 and MERS. The arrangement and chemical composition of the glycans at the 22 N-glycosylation sites of SARS-CoV-2 spike protein and those at the sialoglycoprotein coating of RBCs allow exploration of specifics as to how virally induced RBC clumping may form. The in vitro and clinical testing of these possibilities can be sharpened by the incorporation of an existing anti-COVID-19 therapeutic that has been found in silico to competitively bind to multiple glycans on SARS-CoV-2 spike protein.

Mitigating SARS-CoV-2 Transmission in Hospitals: A Systematic Literature Review

Objectives: Hospital outbreaks of SARS-CoV-2 infection are dreaded but preventable catastrophes. We review the literature to examine the pattern of SARS-CoV-2 transmission in hospitals and identify potential vulnerabilities to mitigate the risk of infection.

Methods: Three electronic databases (PubMed, Embase and Scopus) were searched from inception to July 27, 2021 for publications reporting SARS-CoV-2 outbreaks in hospital. Relevant articles and grey literature reports were hand-searched.

Results: Twenty-seven articles that described 35 SARS-CoV-2 outbreaks were included. Despite epidemiological investigations, the primary case could not be identified in 37% of outbreaks. Healthcare workers accounted for 40% of primary cases (doctors 17%, followed by ancillary staff 11%). Mortality among infected patients was approximately 15%. By contrast, none of the infected HCWs died. Several concerning patterns were identified, including infections involving ancillary staff and healthcare worker infections from the community and household contacts.

Conclusion: Continuous efforts to train-retrain and enforce correct personal protective equipment use and regular routine screening tests (especially among ancillary staff) are necessary to stem future hospital outbreaks of SARS-CoV-2.

Efficacy of antiviral therapies for COVID-19: a systematic review of randomized controlled trials

BACKGROUND

Coronavirus disease 2019 (COVID-19) continues to pose a significant threat to public health worldwide. The purpose of this study was to review current evidence obtained from randomized clinical trials on the efficacy of antivirals for COVID-19 treatment.

METHODS

A systematic literature search was performed using PubMed to identify randomized controlled trials published up to September 4, 2021 that examined the efficacy of antivirals for COVID-19 treatment. Studies that were not randomized controlled trials or that did not include treatment of COVID-19 with approved antivirals were excluded. Risk of bias was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) method. Due to study heterogeneity, inferential statistics were not performed and data were expressed as descriptive statistics.

RESULTS

Of the 2,284 articles retrieved, 31 (12,440 patients) articles were included. Overall, antivirals were more effective when administered early in the disease course. No antiviral treatment demonstrated efficacy at reducing COVID-19 mortality. Sofosbuvir/daclatasvir results suggested clinical improvement, although statistical power was low. Remdesivir exhibited efficacy in reducing time to recovery, but results were inconsistent across trials.

CONCLUSIONS

Although select antivirals have exhibited efficacy to improve clinical outcomes in COVID-19 patients, none demonstrated efficacy in reducing mortality. Larger RCTs are needed to conclusively establish efficacy.

Ivermectin in COVID-19 Management: What is the current evidence?

Ivermectin (IVM), an approved anthelminthic drug, has been reported to have antiviral, antibacterial, and anticancer activities. Antiviral activity is due to the inhibition of nuclear cargo importin (IMP) protein. The anti-SARS CoV-2 activity through in vitro study was first reported by an Australian team. Later, many studies were conducted, and most of the study results were available as non-peer reviewed preprints. In this narrative review, literature on the clinical studies conducted with ivermectin from published articles, preprints, and unpublished evidence are collected till 13th June 2021 and they are discussed based on the severity of COVID-19 disease. Out of the 23 peer-reviewed published articles, 13 studies were randomized controlled trials and the remaining were either prospective interventional, prospective observational, retrospective cohort, cross-sectional, or case series type of studies; additionally, there were 10 randomized controlled trials available as preprints. In most of the studies, ivermectin was used in combination with doxycycline, azithromycin or other drugs. Some of the studies suggested either higher dose and/ or increased duration of ivermectin use to achieve favorable effects. In this review, articles on the prophylactic role of ivermectin in COVID-19 are also discussed - wherein the results are more promising. Despite accumulating evidence suggest the possible use of ivermectin, the final call to incorporate ivermectin in the management of COVID-19 is still inconclusive.